July 24, 2012 |
Do polar bears face obliteration as a species, not from starvation as the northern ice melts but through interbreeding with brown bears as changes in the climate bring them into contact with each other? Authors of a new report say that's a distinct possibility. The closest relative of the polar bear is the brown bear - matings between grizzlies and polar bears sometimes happen in zoos or the wild, yielding very rare examples of hybrids known as grolar bears or pizzlies. Webb Miller of Pennsylvania State University and colleagues set out to examine the timing of the divergence between the two species, using a whole mess of DNA data - from contemporary brown bears, polar bears and black bears as well as from a polar bear that lived 110,000 to 130,000 years ago. (The ancient DNA was obtained from a jawbone found in Norway.)
April 3, 2013 |
Let that long-held breath out, folks. The Alpha Magnetic Spectrometer has picked up a lot of mysterious antimatter in low Earth orbit - but that doesn't necessarily mean it's a sign of dark matter. In fact, even with the 400,000 positrons picked up by the cosmic-ray experiment -- the largest number of such particles ever analyzed in space -- it's unclear whether those positrons result from decaying dark matter, or simply from pulsars sending particles into the universe. "What you have probably seen from the data is a significant new measurement," said Brown University physicist Richard Gaitskell, a lead scientist on a different dark matter detector called the Large Underground Xenon experiment.
March 20, 2013 |
Ladies and gentlemen, the Voyager 1 spacecraft has left the solar system - or has it? Scientists are continuing to debate whether the lonesome craft has finally escaped the solar system after 35 years of travel or has simply entered a previously unknown region of solar influence. On Wednesday, a study published in Geophysical Research Letters , a journal of the American Geophysical Union, suggests that the Voyager spacecraft exited the heliosphere - that region of space dominated by solar winds and long considered to be the edge of the solar system - on Aug. 25, 2012.
July 7, 2012 |
Bipedal robots, in general, are a pretty stilted bunch. Their movements are overarticulated, they wobble, they topple, and when faced with an obstacle -- even one as slight as a slope change -- they often can't overcome it. But that may soon change. This week, researchers from the Univeristy of Arizona published a paper in the Journal of Neural Engineering that describes the development of a new type of robot legs that mimic the neuromuscular architecture of human walking.
August 28, 2013 |
Scientists have caught the first images of a boa constrictor consuming a 9-pound howler monkey, and they are gruesome. In the gallery above, you will see the boa constrictor ingesting the monkey head-first, bit by bit. The images accompany a study describing a play by play of the snake attack published in the journal Primates by Julio Cesar Bicca-Marques of Pontifical Catholic University of Rio Grande do Sul and his student ...
September 4, 2013 |
Screaming at your teenagers to discipline them can make their behavior worse - even if you otherwise have a warm family relationship, researchers say. The effects were comparable to those in studies that focused on physical punishments, the researchers said. “From that we can infer that these results will last the same way that the effects of physical discipline do,” the lead researcher, Ming-Te Wang, an assistant professor of psychology in education at the University of Pittsburgh, said in a statement.
February 1, 2013 |
Scientists have infused "life" into inanimate chemical compounds by flashing a blue-violet light that prompted them to assemble themselves into a crystal. The feat, described in a study published online Thursday by the journal Science, marks an important step toward creating "active" materials that can repair themselves, such as a smartphone screen that fixes its own cracks or a Kevlar vest that fills a hole made by a bullet, experts said. Showing that microscopic particles can be made to come together or break apart on their own "opens a new area for design and production of novel and moving structures," wrote the study authors, a team of physicists and chemists from New York University and Brandeis University in Waltham, Mass.
January 28, 2013 |
A team of storm-chasing scientists sampling rarefied air has found a world of bacteria and fungi floating about 30,000 feet above Earth. The findings, detailed Monday in the Proceedings of the National Academy of Sciences, suggest that microbes have the potential to affect the weather. Scientists have long studied airborne bacteria, but they typically do so from the ground, often trekking to mountain peaks to examine microbes in fresh snow. Beyond that, they don't know much about the number and diversity of floating microbes, said study coauthor Athanasios Nenes, an atmospheric scientist at Georgia Tech.
September 5, 2013 |
WASHINGTON -- The Smithsonian National Zoo announced Thursday that the giant panda cub born there two weeks ago is a girl, is very chatty and "has a fat little belly. " Scientists confirmed the sex of the cub, which was born to Mei Xiang (pronounced may-SHONG) on Aug. 23, according to a news release. DNA tests also showed that the zoo's panda Tian Tian (t-YEN t-YEN) is the father of the cub. Mei Xiang was artificially inseminated twice in late March, with sperm from Tian Tian and from a panda named Gao Gao at the San Diego Zoo, after unsuccessful natural breeding attempts with Tian Tian.
CALIFORNIA | LOCAL
March 18, 2014 |
A group of scientists warned Tuesday that world leaders must act more swiftly to slow greenhouse gas emissions or risk "abrupt, unpredictable and potentially irreversible changes" from climate change. The American Assn. for the Advancement of Science's blunt report contains no new scientific conclusions. But by speaking in plain, accessible terms it seeks to instill greater urgency in leaders and influence everyday Americans. Scientists said many previous assessments have been long and ponderous, and have failed to shift public opinion on global warming.